<template>
    <div style='padding: 10px; margin-bottom: 50px'>
        <el-row>
            <el-col :span='4'>
                <el-card style='width: 300px; height: 300px; color: #333'>
                    <div style='padding-bottom: 10px; border-bottom: 1px solid #ccc'>在线用户<span
                        style='font-size: 12px'>（点击聊天气泡开始聊天）</span></div>
                    <div style='padding: 10px 0' v-for='user in users' :key='user.username'>
                        <span>{{ user.username }}</span>
                        <i class='el-icon-chat-dot-round' style='margin-left: 10px; font-size: 16px; cursor: pointer'
                           @click='chonseUser(user.username)'></i>
                        <!--               @click="chatUser = user.username"></i>-->

                        <span style='font-size: 12px;color: limegreen; margin-left: 5px'
                              v-if='user.username === chatUser'>chatting...</span>
                    </div>
                </el-card>
            </el-col>
            <el-col :span='20'>
                <div style='width: 800px; margin: 0 auto; background-color: white;
                    border-radius: 5px; box-shadow: 0 0 10px #ccc'>
                    <div style='text-align: center; line-height: 50px;'>
                        Web聊天室（{{ chatUser }}）
                    </div>
                    <div style='height: 350px; overflow:auto; border-top: 1px solid #ccc' v-html='content'></div>
                    <div style='height: 200px'>
            <textarea v-model='text' style='height: 160px; width: 740px; padding: 20px; border: none; border-top: 1px solid #ccc;
             border-bottom: 1px solid #ccc; outline: none'></textarea>
                        <div style='text-align: right; padding-right: 10px'>
                            <el-button type='primary' size='mini' @click='send'>发送</el-button>
                        </div>
                    </div>
                </div>
            </el-col>
        </el-row>
    </div>
</template>
<script>

let socket;
export default {
    name: 'Im',
    data() {
        return {
            circleUrl: 'https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png',
            // 自己
            user: {},
            isCollapse: false,
            // 目标list
            users: [],
            // 选中的目标
            chatUser: '',
            text: '',
            messages: [],
            content: ''
        };
    },
    created() {
        this.init();
    },
    methods: {
        chonseUser(toUser){
            this.chatUser=toUser
            console.log("from->"+this.user+",to->"+toUser)
            this.$http.get("/chat/getChatRecords/"+this.user+"/"+toUser).then(resp=>{
                resp.data.data.forEach(e=>{
                    this.createContent(e.tos,e.froms,e.msg)
                })
            })
        },
        send() {
            if (!this.chatUser) {
                this.$message({ type: 'warning', message: '请选择聊天对象' });
                return;
            }
            if (!this.text) {
                this.$message({ type: 'warning', message: '请输入内容' });
            } else {
                if (typeof (WebSocket) == 'undefined') {
                    console.log('您的浏览器不支持WebSocket');
                } else {
                    console.log('您的浏览器支持WebSocket');
                    // 组装待发送的消息 json
                    // {"from": "zhang", "to": "admin", "text": "聊天文本"}
                    let message = { from: this.user.username, to: this.chatUser, text: this.text };
                    socket.send(JSON.stringify(message));  // 将组装好的json发送给服务端，由服务端进行转发
                    this.messages.push({ user: this.user, text: this.text });
                    // 构建消息内容，本人消息
                    this.createContent(null, this.user, this.text);
                    this.text = '';
                }
            }
        },
        createContent(remoteUser, nowUser, text) {  // 这个方法是用来将 json的聊天消息数据转换成 html的。
            let html;
            // 当前用户消息
            if (nowUser==this.user) { // nowUser 表示是否显示当前用户发送的聊天消息，绿色气泡
                html = '<div class="el-row" style="padding: 5px 0">\n' +
                    '  <div class="el-col el-col-22" style="text-align: right; padding-right: 10px">\n' +
                    '    <div class="tip left">' + text + '</div>\n' +
                    '  </div>\n' +
                    '  <div class="el-col el-col-2">\n' +
                    '  <span class="el-avatar el-avatar--circle" style="height: 40px; width: 40px; line-height: 40px;">\n' +
                    '    <img src="https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png" style="object-fit: cover;">\n' +
                    '  </span>\n' +
                    '  </div>\n' +
                    '</div>';
            } else  {   // remoteUser表示远程用户聊天消息，蓝色的气泡
                html = '<div class="el-row" style="padding: 5px 0">\n' +
                    '  <div class="el-col el-col-2" style="text-align: right">\n' +
                    '  <span class="el-avatar el-avatar--circle" style="height: 40px; width: 40px; line-height: 40px;">\n' +
                    '    <img src="https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png" style="object-fit: cover;">\n' +
                    '  </span>\n' +
                    '  </div>\n' +
                    '  <div class="el-col el-col-22" style="text-align: left; padding-left: 10px">\n' +
                    '    <div class="tip right">' + text + '</div>\n' +
                    '  </div>\n' +
                    '</div>';
            }
            this.content += html;
        },
        init() {
            this.user = localStorage.getItem("user");
            console.log(this.user);
            let username = this.user;
            let _this = this;
            if (typeof (WebSocket) == 'undefined') {
                console.log('您的浏览器不支持WebSocket');
            } else {
                console.log('您的浏览器支持WebSocket');
                let socketUrl = 'ws://localhost:8081/chatserver/' + username;
                if (socket != null) {
                    socket.close();
                    socket = null;

                }
                // 开启一个websocket服务
                socket = new WebSocket(socketUrl);
                //打开事件
                socket.onopen = function() {
                    console.log('websocket已打开');
                };
                //  浏览器端收消息，获得从服务端发送过来的文本消息
                socket.onmessage = function(msg) {
                    console.log('收到数据====' + msg.data);
                    let data = JSON.parse(msg.data);  // 对收到的json数据进行解析， 类似这样的： {"users": [{"username": "zhang"},{ "username": "admin"}]}
                    if (data.users) {  // 获取在线人员信息
                        _this.users = data.users.filter(user => user.username !== username);  // 获取当前连接的所有用户信息，并且排除自身，自己不会出现在自己的聊天列表里
                    } else {
                        // 如果服务器端发送过来的json数据 不包含 users 这个key，那么发送过来的就是聊天文本json数据
                        //  // {"from": "zhang", "text": "hello"}
                        _this.chatUser = data.from;
                        // if (data.from === _this.chatUser) {
                        _this.messages.push(data);
                        // 构建消息内容
                        _this.createContent(data.from, null, data.text);
                    }
                    // }
                };
                //关闭事件
                socket.onclose = function() {
                    console.log('websocket已关闭');
                };
                //发生了错误事件
                socket.onerror = function() {
                    console.log('websocket发生了错误');
                };
            }
        }
    }
};
</script>
<style>
.tip {
    color: white;
    text-align: center;
    border-radius: 10px;
    font-family: sans-serif;
    padding: 10px;
    width: auto;
    display: inline-block !important;
    display: inline;
}

.right {
    background-color: deepskyblue;
}

.left {
    background-color: forestgreen;
}
</style>
